Optimizing Hormonal Induction and Water Quality Parameters for Enhanced Reproductive Success in Grass Carp (Ctenopharyngodon idella)

This study optimizes hormonal induction techniques and water quality parameters to improve reproductive success in Grass Carp (Ctenopharyngodon idella). Conducted over a year at Bismillah Fish Seed Production Center, Bangladesh, key reproductive indicators including gonadosomatic index (GSI) and hepatosomatic index (HSI) were monitored. Peak values were observed in March, with females showing a GSI of 21.48±2.69% and an HSI of 8.03±1.83%, and males at 1.37±0.38% (GSI) and 4.68±0.23% (HSI). Six hormonal treatments (CPG, HCG, Ovupin, and combinations) were tested. Ovulation rates ranged from 47% to 95%, with Ovupin inducing the shortest ovulation period (5.48 hours) and HCG the longest (7.18 hours). Fertilization rates varied from 65.74% to 93.48%, with CPG (T1) achieving the highest fertilization (93.48±5.83%) and hatching rate (89.36±7.26%). Larval survival rates after 48 hours were highest with CPG (73.9±3.79%) and lowest with HCG (32.5±2.14%). Optimal water quality parameters contributed to successful breeding. The study concludes that CPG and Ovupin + CPG are the most effective protocols for enhancing Grass Carp reproduction.